Multi-luminous element and method for manufacturing same

ABSTRACT

The present invention relates to a multi-luminous element and a method for manufacturing the same. The present invention provides the multi-luminous element comprising: a buffer layer disposed on a substrate; a first type semiconductor layer disposed on the buffer layer; a first active layer which is disposed on the first type semiconductor layer and is patterned to expose a part of the first type semiconductor layer; a second active layer disposed on the first type semiconductor layer which is exposed by the first active layer; and a second type semiconductor layer disposed on the first active layer and the second active layer, the first and second active layers being repeatedly disposed in the horizontal direction, and the method for manufacturing the same.

CROSS REFERENCE TO RELATED APPLICATION

This application claims the priority of Korean Patent Application No.10-2010-0023611, filed on Mar. 17, 2010 in the KIPO (Korean IntellectualProperty Office). Further, this application is the National Phaseapplication of International Application No. PCT/KR2011/001813 filedMar. 15, 2011, which designates the United States and was published inKorean.

TECHNICAL FIELD

The present invention relates generally to a luminous element and amethod for manufacturing the same and, more particularly, to amulti-luminous element and related manufacturing method in which thefirst and second active layers are repeatedly disposed in a horizontaldirection to reduce loss of luminous efficiency.

BACKGROUND ART

LED (Light Emitting Diode) is a sort of semiconductor device thatconverts an electric current into a light, and is used as a light sourcefor illumination or display devices. In comparison with a conventionallight source, LED has relatively excellent characteristics such as anultra-small size, low power consumption, a long life, a fast reactiontime, and the like. Additionally, no use of mercury or any otherdischarge gas is environmentally friendly.

Meanwhile, LED is used as a white light source, which is formed of acombination of red, green and blue LEDs, a combination of a blue LED andyellow phospher, or a combination of an UV LED and RGB phospher.

However, use of a conventional LED for a white light source may cause acomplex structure, a complicated manufacturing process, a poor luminousefficiency, or the like.

DETAILED DESCRIPTION OF THE INVENTION Technical Problems

Accordingly, an object of the present invention is to provide amulti-luminous element having reduced loss of luminous efficiency and amethod for manufacturing the same.

Another object of the present invention is to provide a multi-luminouselement and manufacturing method in which the first active layer foremitting a light with the first wavelength and the second active layerfor emitting a light with the second wavelength are repeatedly disposedin a horizontal direction.

Technical Solutions

In order to accomplish the above objects, one aspect of the presentinvention provides a multi-luminous element that comprises a bufferlayer located on a substrate; a first type semiconductor layer locatedon the buffer layer; a first active layer located on the first typesemiconductor layer and patterned to expose a part of the first typesemiconductor layer; a second active layer located on the first typesemiconductor layer exposed by the first active layer; and a second typesemiconductor layer located on the first active layer and the secondactive layer, wherein the first active layer and the second active layerare repeatedly disposed side by side.

The multi-luminous element may further comprise a seed layer locatedbetween the buffer layer and the first type semiconductor layer.

The buffer layer may include AlN or GaN.

The first type semiconductor layer may include N-type GaN ohmic contactlayer.

The second active layer may be divided into at least two sections whichare separated by the first active layer.

The first active layer or the second active layer may have a multiplequantum wells (MQWs) structure.

The first active layer may include at least one barrier layer and atleast one well layer which are stacked by turns. The barrier layer mayinclude Al_(x1)Ga_(1-x1-y1)In_(1-x1)N(0<x1<1, 0<y1<1, x1+y1<1), and thewell layer may include Al_(x2)Ga_(1-x2-y2)In_(1-x2)N(0<x2<1, 0<y2<1,x2+y2<1, x2<x1, y2<y1).

The second active layer may include at least one barrier layer and atleast one well layer which are stacked by turns. The barrier layer mayinclude Al_(x3)Ga_(1-x3-y3)In_(1-x3)N(0<x3<1, 0<y3<1, x3+y3<1), and thewell layer may include Al_(x4)Ga_(1-x4-y4)In_(1-x4)N(0<x4<1, 0<y4<1,x4+y4<1, x4<x3, y4<y3).

The first active layer may include at least one barrier layer and atleast one well layer which are stacked by turns, and the second activelayer may include at least one barrier layer and at least one well layerwhich are stacked by turns. The barrier layer may have a thickness of 5to 15 nm and the well layer may have a thickness of 1 to 3 nm.

The first active layer may be patterned to expose a part of the firsttype semiconductor layer in the form of a linear type pattern having aspecific width, a circular type pattern having a specific diameter, or apolygonal type pattern including a rectangular type pattern having aspecific breadth, in a plan view.

The multi-luminous element may further comprise a mask pattern locatedbetween the first active layer and the second type semiconductor layer.

The mask pattern may include SiO₂.

In the multi-luminous element, light with the third wavelength may beproduced by interference between light with the first wavelength emittedfrom the first active layer and light with the second wavelength emittedfrom the second active layer.

The width, diameter or breadth of the first active layer may satisfy aspecific condition λ₁/4n₁ (here, λ₁ denotes the first wavelength oflight emitted from the first active layer, and n₁ means a refractiveindex of the first active layer), and the width, diameter or breadth ofthe second active layer may satisfy a specific condition λ₂/4n₂ (here,λ₂ denotes the second wavelength of light emitted from the second activelayer, and n₂ means a refractive index of the second active layer).

The second type semiconductor layer may include P-type GaN ohmic contactlayer.

In order to accomplish the above objects, another aspect of the presentinvention provides a method for manufacturing a multi-luminous element,the method comprising steps of sequentially stacking a buffer layer, afirst type semiconductor layer, and a first active layer on a substrate;forming a patterned first active layer by etching the first active layerto expose a part of the first type semiconductor layer; forming a secondactive layer over the substrate where the patterned first active layeris formed; and forming a second type semiconductor layer on thepatterned first active layer and the second active layer, wherein thesecond active layer is formed on the part of the first typesemiconductor layer exposed by the patterned first active layer, andwherein the first active layer and the second active layer arerepeatedly disposed side by side.

The step of forming the patterned first active layer may include stepsof stacking a mask layer on the first active layer; forming a maskpattern by patterning the mask layer; and forming the patterned firstactive layer by etching the first active layer through the mask patternso as to expose the part of the first type semiconductor layer.

The buffer layer may be formed in a temperature atmosphere of 450 to600° C. The first type semiconductor layer or the second typesemiconductor layer may be formed in a temperature atmosphere of 1000 to1100° C. The first active layer or the second active layer may be formedin a temperature atmosphere of 700 to 850° C.

The method may further comprise step of, in the sequentially stackingstep, forming a seed layer between the buffer layer and the first typesemiconductor layer.

Also, the method may further comprise step of, between the step offorming the second active layer and the step of forming the second typesemiconductor layer, removing the mask pattern.

Advantageous Effects

The present invention accomplishes the above discussed objects.Specifically, according to this invention, by repeatedly disposing thefirst and second active layers side by side, a multi-luminous elementhaving reduced loss of luminous efficiency and capable of producingmulti-wavelength is advantageously provided together with a method formanufacturing the same.

Furthermore, according to this invention, a multi-luminous elementhaving a laterally repeated disposition in a plan view is providedtogether with a related manufacturing method.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a cross-sectional view illustrating the structure of amulti-luminous element in accordance with an embodiment of the presentinvention.

FIGS. 2 to 4 are cross-sectional views illustrating a process ofmanufacturing a multi-luminous element in accordance with an embodimentof the present invention.

FIGS. 5 to 7 are plan views illustrating forms of the patterned firstactive layer.

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiments of the present invention will now be described more fullywith reference to the accompanying drawings. This invention may,however, be embodied in many different forms and should not be construedas limited to the exemplary embodiments set forth herein. Rather, thedisclosed embodiments are provided so that this disclosure will bethorough and complete, and will fully convey the scope of the inventionto those skilled in the art. In the drawings, the thickness of layersand regions is exaggerated for clarity. In this disclosure, likereference numerals represent like parts.

FIG. 1 is a cross-sectional view illustrating the structure of amulti-luminous element in accordance with an embodiment of the presentinvention.

Referring to FIG. 1, the multi-luminous element 100 may include asubstrate 110, a buffer layer 120, a seed layer 130, a first typesemiconductor layer 140, a patterned first active layer 152, a maskpattern 162, a second active layer 170, and a second type semiconductorlayer 180.

Alternatively, if necessary, the multi-luminous element 100 may not havethe seed layer 130 or the mask pattern 162.

The substrate 110 may be Al₂O₃ substrate, Si substrate, SiC substrate,GaAs substrate, or sapphire substrate, and may be preferably sapphiresubstrate.

The buffer layer 120 may be located between the substrate 110 and theseed layer 130 or the first type semiconductor layer 140 in order toreduce a difference in lattice constant or in coefficient of thermalexpansion with an upper layer. Therefore, the buffer layer 120 may beformed of any material capable of reducing a difference in latticeconstant or in coefficient of thermal expansion, preferably includingAlN or GaN.

The seed layer 130 may be located on the buffer layer 120. The seedlayer 130 may be μ-GaN layer, which may be formed of undopped GaN.

The first type semiconductor layer 140 may be located on the bufferlayer 120 or on the seed layer 130. The first type semiconductor layer140 may be a semiconductor layer including nitride, for example,including GaN, Al_(x)Ga_(1-x)N(0<x<1), In_(x)Ga_(1-x)N(0<x<1), orIn_(x)Al_(y)Ga_(1-(x+y))N(0<x<1, 0<y<1, x+y<1), preferably includingGaN. Here, GaN may be N-type GaN doped with N-type impurities,especially N-type GaN ohmic contact layer doped with Si.

The patterned first active layer 152 may have a quantum well structure,preferably a multiple quantum wells (MQWs) structure. Namely, thepatterned first active layer 152 includes at least one barrier layer(not shown) and at least one well layer (not shown), which may bestacked by turns. The patterned first active layer 152 is formed toexpose a part of the first type semiconductor layer 140. The barrierlayer of the patterned first active layer 152 may includeAl_(x1)Ga_(1-x1-y1)In_(1-x1)N(0<x1<1, 0<y1<1, x1+y1<1), and the welllayer of the patterned first active layer 152 may includeAl_(x2)Ga_(1-x2-y2)In_(1-x2)N(0<x2<1, 0<y2<1, x2+y2<1, x2<x1, y2<y1).The barrier layer of the patterned first active layer 152 may be formedwith a thickness of 5 to 15 nm, and the well layer of the patternedfirst active layer 152 may be formed with a thickness of 1 to 3 nm.

The mask pattern 162 may be located on the patterned first active layer152. The mask pattern 162 may be formed of any material capable ofproducing a pattern, preferably formed of SiO₂, with a thickness of 50to 200 nm, preferably with a thickness of 100 nm. The mask pattern 162is used as a mask for forming the patterned first active layer 152, sothat the shape of the patterned first active layer 152 may be determineddepending on the mask pattern 162. As shown in FIGS. 5 to 7 to bediscussed later, the mask pattern 162 may be formed with one of a lineartype pattern 162 a having a specific width in a plan view, a circulartype pattern 162 b having a specific diameter in a plan view, and apolygonal type pattern such as a rectangular type pattern 162 c having aspecific breadth in a plan view. Therefore, the first active layer 152may be patterned to expose a part of the underlying first typesemiconductor layer 140 in the form of a linear type having a specificwidth, a circular type having a specific diameter, or a polygonal typesuch as a rectangular type having a specific breadth, in a plan view.

The patterned first active layer 152 may be formed with patterns havinga width, diameter or breadth between 10 nm and 10 μm, which may bedetermined depending on the first wavelength of light emitted from thefirst active layer 152. This width, diameter or breadth of the patternedfirst active layer 152 may be determined to satisfy a specific conditionλ₁/4n₁. Here, λ₁ denotes the first wavelength of light emitted from thepatterned first active layer 152, and n₁ means a refractive index of thepatterned first active layer 152. For example, if the first wavelengthof light emitted from the patterned first active layer 152 is 500 nm,and if a refractive index of the patterned first active layer 152 is2.5, the width, diameter or breadth of the patterned first active layer152 may be 500 nm/(4×2.5), i.e., 50 nm.

The second active layer 170 may be located on the first typesemiconductor layer 140, more exactly, on a part of the first typesemiconductor layer 140 exposed by the patterned first active layer 152.Namely, the second active layer 170 and the patterned first active layer152 may be located side by side and repeatedly disposed in a horizontaldirection. The second active layer 170 may be divided into at least twosections by the patterned first active layer 152, and adjacent twosections of the second active layer 170 may be separated by thepatterned first active layer 152. That is to say, the patterned firstactive layer 152 may also be divided into at least two sections by thesecond active layer 170, and adjacent two sections of the patternedfirst active layer 152 may be separated by the second active layer 170.

The second active layer 170 may have a quantum well structure,preferably a multiple quantum wells (MQWs) structure. Namely, the secondactive layer 170 includes at least one barrier layer (not shown) and atleast one well layer (not shown), which may be stacked by turns. Thebarrier layer of the second active layer 170 may includeAl_(x3)Ga_(1-x3-y3)In_(1-x3)N(0<x3<1, 0<y3<1, x3+y3<1), and the welllayer of the second active layer 170 may includeAl_(x4)Ga_(1-x4-y4)In_(1-x4)N(0<x4<1, 0<y4<1, x4+y4<1, x4<x3, y4<y3).The barrier layer of the second active layer 170 may be formed with athickness of 5 to 15 nm, and the well layer of the second active layer170 may be formed with a thickness of 1 to 3 nm.

The second active layer 170 may be formed with patterns having a width,diameter or breadth between 10 nm and 10 μm, which may be determineddepending on the second wavelength of light emitted from the secondactive layer 170. This width, diameter or breadth of the second activelayer 170 may be determined to satisfy a specific condition λ₂/4n₂.Here, λ₂ denotes the second wavelength of light emitted from the secondactive layer 170, and n₂ means a refractive index of the second activelayer 170. For example, if the second wavelength of light emitted fromthe second active layer 170 is 300 nm, and if a refractive index of thesecond active layer 170 is 2.5, the width, diameter or breadth of thesecond active layer 170 may be 300 nm/(4×2.5), i.e., 30 nm.

The second active layer 170 may emit light having the second wavelengthwhich is different from the wavelength of light emitted from thepatterned first active layer 152. Although having the same constituents,the first and second active layers 152 and 170 may emit light with thefirst wavelength and light with the second wavelength, respectively, byvarying the ratio of Al to In or Ga. Here, according as the ratio of Alincreases in comparison with the ratio of In or Ga, the wavelength oflight emitted is decreased. Therefore, in order for the patterned firstactive layer 152 to emit light having a longer wavelength in comparisonwith the second active layer 170, the patterned first active layer 152may be formed to have a lower ratio of In or Ga to Al in comparison withthe second active layer 170.

The second type semiconductor layer 180 may be a semiconductor layerincluding nitride, for example, including GaN, Al_(x)Ga_(1-x)N(0<x<1),In_(x)Ga_(1-x)N(0<x<1), or In_(x)Al_(y)Ga_(1-(x+y))N(0<x<1, 0<y<1,x+y<1), preferably including GaN. Here, GaN may be P-type GaN ohmiccontact layer doped with P-type impurities. The second typesemiconductor layer 180 may be located on the patterned first activelayer 152 and the second active layer 170. While the second typesemiconductor layer 180 may be in a direct contact with the secondactive layer 170, the mask pattern 162 may be interposed between thesecond type semiconductor layer 180 and the patterned first active layer152. If the mask pattern 162 is not included, the second typesemiconductor layer 180 may be in a direct contact with both of thepatterned first active layer 152 and the second active layer 170.

An electrical connection, i.e., a flow of current, among the first typesemiconductor layer 140, the patterned first active layer 152, thesecond active layer 170, and the second type semiconductor layer 180 mayvary depending on whether the mask pattern 162 is included or not. Ifthe mask pattern 162 is not existent, there are three paths, namely, apath connected by the first type semiconductor layer 140, the patternedfirst active layer 152, and the second type semiconductor layer 180, apath connected by the first type semiconductor layer 140, the secondactive layer 170, and the second type semiconductor layer 180, and apath connected by the first type semiconductor layer 140, the patternedfirst active layer 152, the second active layer 170, and the second typesemiconductor layer 180. In contrast, if the mask pattern 162 isexistent, the mask pattern 162 acts as an insulating layer and thusthere are two paths, namely, a path connected by the first typesemiconductor layer 140, the second active layer 170, and the secondtype semiconductor layer 180, and a path connected by the first typesemiconductor layer 140, the patterned first active layer 152, thesecond active layer 170, and the second type semiconductor layer 180.

Therefore, since the first and second active layers 152 and 170 whichrespectively emit lights with different wavelengths are repeatedlydisposed side by side, the multi-luminous element 100 of an embodimenthas the advantage of capability to produce multi-wavelength without lossof luminous efficiency. In this multi-luminous element 100, each of thepatterned first active layer 152 and the second active layer 170 may beformed with a quantum well structure.

Among the light emitted from the patterned first active layer 152, lightemitted in a vertical direction from the patterned first active layer152 advances in an upward or downward direction of the multi-luminouselement 100. However, light emitted in a horizontal direction, namelyemitted laterally, from the patterned first active layer 152 advances inother form. Specifically, light emitted laterally from the patternedfirst active layer 152 meets a surface of the second active layer 170 ona transmission path of light. The patterned first active layer 152 andthe second active layer 170 have different refractive indexes due todifferent ratios of constituents. Therefore, light emitted from thepatterned first active layer 152 is refracted or reflected at thesurface of the second active layer 170. Since the width, diameter orbreadth of the patterned first active layer 152 satisfies a specificcondition λ₁/4n₁ as discussed above, laterally transmitted light fromthe patterned first active layer 152 is amplified. As a result, thelight extraction efficiency of the patterned first active layer 152 isenhanced.

The same applies to the second active layer 170. Specifically, lightemitted in a vertical direction from the second active layer 170advances in an upward or downward direction of the multi-luminouselement 100, and light emitted from the second active layer 170 isrefracted or reflected at the surface of the patterned first activelayer 152. Since the width, diameter or breadth of the second activelayer 170 satisfies a specific condition λ₂/4n₂ as discussed above,laterally transmitted light from the second active layer 170 isamplified. As a result, the light extraction efficiency of the secondactive layer 170 is enhanced.

Meanwhile, there may occur interference between light emitted from thepatterned first active layer 152 and light emitted from the secondactive layer 170. Therefore, light with third wavelength caused by acombination of the first wavelength of light emitted from the patternedfirst active layer 152 and the second wavelength of light emitted fromthe second active layer 170 may be extracted.

Additionally, the multi-luminous element 100 of an embodiment mayextract light with various colors. Namely, depending on the firstwavelength of light emitted from the patterned first active layer 152and the second wavelength of light emitted from the second active layer170, the multi-luminous element 100 may extract light having variouscolors such as red, green or blue and also extract white light or otherlight such as ultraviolet light or infrared light. This extraction oflight having various wavelengths may cause the possibility of beingapplied to various fields.

For example, if the multi-luminous element 100 is used as a light sourcefor the growth of plants, light having a wavelength corresponding toblue (Blue light is believed to promote the formation of leaves ofplants.) may be extracted from the patterned first active layer 152, andlight having a wavelength corresponding to red (Red light is believed topromote photosynthesis.) or light having a wavelength corresponding toultraviolet (UV light is believed to make the leaves of plants thick orto promote the color formation of pigment.) may be extracted from thesecond active layer 170. In this case, the patterned first active layer152 may have the well layer composed of 2% Al, 76% Ga, and 22% In so asto extract light with 460 nm wavelength corresponding to blue. Thesecond active layer 170 may have the well layer composed of 0.5% Al,49.5% Ga, and 50% In so as to extract red light with 650 nm wavelengthor have the well layer composed of 6% Al, 86% Ga, and 8% In so as toextract UV light with 380 nm wavelength.

Additionally, in order to use the multi-luminous element 100 as a whitelight source, the patterned first active layer 152 may extract yellowlight and the second active layer 170 may extract blue light. In thiscase, the patterned first active layer 152 may have 0.8% Al, 59.2% Ga,and 40% In so as to extract yellow light, and the second active layer170 may have 2% Al, 76% Ga, and 22% In so as to extract blue light.

Although in the above-discussed embodiment the multi-luminous element100 includes two active layers only, it is possible to have three ormore active layers which emit light with different wavelengths.

FIGS. 2 to 4 are cross-sectional views illustrating a process ofmanufacturing a multi-luminous element in accordance with an embodimentof the present invention.

FIGS. 5 to 7 are plan views illustrating forms of the patterned firstactive layer.

Referring to FIGS. 2 to 7, a method for manufacturing a multi-luminouselement according to an embodiment begins with preparing the substrate110.

The substrate 110 may be Al₂O₃ substrate, Si substrate, SiC substrate,GaAs substrate, or sapphire substrate, and may be preferably sapphiresubstrate (Al₂O₃ substrate).

Next, the buffer layer 120, the seed layer 130, the first typesemiconductor layer 140, a first active layer 150, and a mask layer 160are sequentially stacked on the substrate 110.

Each of the buffer layer 120, the seed layer 130, the first typesemiconductor layer 140, the first active layer 150, and the mask layer160 may be formed using physical vapor deposition or chemical vapordeposition such as sputtering, PECVD (Plasma Enhanced Chemical VaporDeposition), MOCVD (Metal Organic Chemical Vapor Deposition), ALD(Atomic Layer Deposition), MBE (Molecular Beam Epitaxy), and HVPE(Hybrid Vapor Phase Epitaxy).

The buffer layer 120 may be formed of nitride including AlN or GaN, andthe seed layer 130 may be formed of undopped μ-GaN.

The first type semiconductor layer 140 may be a semiconductor layerincluding nitride, for example, including GaN, Al_(x)Ga_(1-x)N(0<x<1),In_(x)Ga_(1-x)N(0<x<1), or In_(x)Al_(y)Ga_(1-(x+y))N(0<x<1, 0<y<1,x+y<1), preferably including GaN. Here, GaN may be N-type GaN doped withN-type impurities, especially N-type GaN ohmic contact layer doped withSi. The first active layer 150 is formed by stacking at least onebarrier layer with 5 to 15 nm thickness and at least one well layer with1 to 3 nm thickness. The barrier layer may be composed ofAl_(x1)Ga_(1-x1-y1)In_(1-x1)N(0<x1<1, 0<y1<1, x1+y1<1), and the welllayer may be composed of Al_(x2)Ga_(1-x2-y2)In_(1-x2)N(0<x2<1, 0<y2<1,x2+y2<1, x2<x1, y2<y1).

The mask layer 160 may be formed of any material capable of producing apattern, preferably formed of SiO₂, with a thickness of 50 to 200 nm,preferably 100 nm thickness.

It is desirable that the buffer layer 120 is formed in a temperatureatmosphere of 450 to 600° C., the first type semiconductor layer 140 isformed in a temperature atmosphere of 1000 to 1100° C., and the firstactive layer 150 is formed in a temperature atmosphere of 700 to 850° C.

Next, using a patterning process, the mask pattern 162 is formed fromthe mask layer 160. As shown in FIGS. 5 to 7, the mask pattern 162 maybe formed to have at least one of a linear type pattern 162 a having aspecific width in a plan view, a circular type pattern 162 b having aspecific diameter in a plan view, and a polygonal type pattern such as arectangular type pattern 162 c having a specific breadth in a plan viewin order to expose a part of the underlying first type semiconductorlayer 140. The mask pattern 162 is formed to have a width, diameter orbreadth between 10 nm and 10 μm.

Next, by etching the first active layer 150 through the mask pattern162, the patterned first active layer 152 is formed. Namely, the firstactive layer 150 is etched to expose a part of the first typesemiconductor layer 140, thus forming the patterned first active layer152. Preferably, a dry etching which is an anisotropic etching is used.

Next, the second active layer 170 is formed over the substrate 110having the patterned first active layer 150. The second active layer 170is formed by stacking at least one barrier layer with 5 to 15 nmthickness and at least one well layer with 1 to 3 nm thickness. Thebarrier layer may be composed of Al_(x3)Ga_(1-x3-y3)In_(1-x3)N(0<x3<1,0<y3<1, x3+y3<1), and the well layer may be composed ofAl_(x4)Ga_(1-x4-y4)In_(1-x4)N(0<x4<1, 0<y4<1, x4+y4<1, x4<x3, y4<y3).

Like the first active layer 150, the second active layer 170 may beformed in a temperature atmosphere of 700 to 850° C. For example, thesecond active layer 170 may be formed through growth using epitaxialgrowth technique or the like on a part of the first type semiconductorlayer 140 exposed by the patterned first active layer 152. At this time,the second active layer 170 is not formed on the mask pattern 162 sincethe growth of the second active layer 170 is not permitted on the maskpattern 162.

Alternatively, the second active layer 170 may be formed through vapordeposition technique using organic metal such as MOCVD over thesubstrate 110 having the patterned first active layer 152. In this case,the second active layer 170 may be formed on the mask pattern 162 aswell as on the first type semiconductor layer 140 exposed by thepatterned first active layer 152. Therefore, the second active layer 170formed on the mask pattern 162 is removed through wet etching using BOE(Buffer Oxide Etchant) and HF solution or through equipment forplanarization such as CMP (Chemical Mechanical Planarization).

After the second active layer 170 is formed, if necessary, the maskpattern 162 may be removed.

As discussed above, the patterned first active layer 152 and the secondactive layer 170 are formed using the mask pattern 162. However, ifnecessary, three or more active layers may be formed using two or moremask patterns.

Next, the second type semiconductor layer 180 is formed over thesubstrate 110 having the patterned first active layer 152 and the secondactive layer 170. As a result, the multi-luminous element according toan embodiment is obtained.

The second type semiconductor layer 180 may be formed in a temperatureatmosphere of 1000 to 1100° C. The second type semiconductor layer 180may be a semiconductor layer including nitride, for example, includingGaN, Al_(x)Ga_(1-x)N(0<x<1), In_(x)Ga_(1-x)N(0<x<1), orIn_(x)Al_(y)Ga_(1-(x+y))N(0<x<1, 0<y<1, x+y<1), preferably includingGaN. Here, GaN may be P-type GaN ohmic contact layer doped with P-typeimpurities.

While this invention has been particularly shown and described withreference to an exemplary embodiment thereof, it will be understood bythose skilled in the art that various changes in form and details may bemade therein without departing from the spirit and scope of theinvention as defined by the appended claims.

What is claimed is:
 1. A method for manufacturing a multi-luminouselement, the method comprising steps of: sequentially stacking a bufferlayer, a first type semiconductor layer, and a first active layer on asubstrate; forming a patterned first active layer by etching the firstactive layer to expose a part of the first type semiconductor layer;forming a second active layer over the substrate where the patternedfirst active layer is formed; and forming a second type semiconductorlayer on the patterned first active layer and the second active layer,wherein the second active layer is formed on the part of the first typesemiconductor layer exposed by the patterned first active layer, andwherein the first active layer and the second active layer arerepeatedly disposed side by side.
 2. The method of claim 1, wherein thestep of forming the patterned first active layer includes steps of:stacking a mask layer on the first active layer; forming a mask patternby patterning the mask layer; and forming the patterned first activelayer by etching the first active layer through the mask pattern so asto expose the part of the first type semiconductor layer.
 3. The methodof claim 2, wherein the buffer layer is formed in a temperatureatmosphere of 450 to 600° C., wherein the first type semiconductor layeror the second type semiconductor layer is formed in a temperatureatmosphere of 1000 to 1100° C., and wherein the first active layer orthe second active layer is formed in a temperature atmosphere of 700 to850° C.
 4. The method of claim 2, further comprising step of: in thesequentially stacking step, forming a seed layer between the bufferlayer and the first type semiconductor layer.
 5. The method of claim 2,further comprising step of: between the step of forming the secondactive layer and the step of forming the second type semiconductorlayer, removing the mask pattern.